将pdf的url转MultipartFile

要将PDF的URL转换为MultipartFile，您可以使用以下代码：

public static MultipartFile urlToMultipartFile(String url, String fileName) throws Exception {
    File file = null;
    MultipartFile multipartFile = null;
    try {
        HttpURLConnection httpUrl = (HttpURLConnection) new URL(url).openConnection();
        httpUrl.connect();
        file = UrlToMultipartFileUtil.inputStreamToFile(httpUrl.getInputStream(), fileName);
        multipartFile = UrlToMultipartFileUtil.fileToMultipartFile(file);
        httpUrl.disconnect();
    } catch (Exception e) {
        e.printStackTrace();
    }
    return multipartFile;
}

请确保您已经导入`java.net.HttpURLConnection`和`java.net.URL`类，并且`UrlToMultipartFileUtil`类包含了实现`inputStreamToFile`和`fileToMultipartFile`方法的代码。然后，您只需调用`urlToMultipartFile`方法，并将PDF的URL和文件名作为参数传递给它，它将返回一个MultipartFile对象。